Network · AS51100

AS51100 Kier Ltd

AS51100 (Kier Ltd) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS51100

OwnerKier Ltd
KindInternet service provider
Servers, not peopleno
IPv4 addresses1,536
IPv4 ranges2
IPv6 ranges0

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

185.239.164.0/22
91.195.112.0/23

Ranges and owner from DB-IP (CC BY 4.0), updated 2026-10-21.

Check an IP address →

Detect it in code

Spot AS51100 traffic at signup.

Send the visitor's IP. The response includes the ASN, the owner and flags.hosting.

curl https://veqen-app.com/v1/ip/check \
  -H "Authorization: Bearer $VEQEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"ip": "203.0.113.7"}'

import os, requests

r = requests.post(
    "https://veqen-app.com/v1/ip/check",
    headers={"Authorization": f"Bearer {os.environ['VEQEN_API_KEY']}"},
    json={"ip": "203.0.113.7"},
    timeout=10,
)
result = r.json()
print(result["risk"]["verdict"], result["risk"]["reasons"])

const res = await fetch("https://veqen-app.com/v1/ip/check", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.VEQEN_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({"ip": "203.0.113.7"}),
});
const result = await res.json();
console.log(result.risk.verdict, result.risk.reasons);

Questions

About AS51100

Is AS51100 a datacenter or VPN network?

AS51100 (Kier Ltd) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS51100?

AS51100 is registered to Kier Ltd. It announces about 1,536 IPv4 addresses.

How do I detect traffic from AS51100?

Call the Veqen IP check with the visitor's address. The response includes the ASN, the owner and whether the network is a datacenter, VPN network, relay or ISP.